1. Field of the Invention
The present invention relates to business television and video conferencing systems. More particularly, the present invention relates to a programmable digital switch for use in controlling video teleconferencing systems as well as business television systems independently or simultaneously with a single room or studio coordinator/controller.
2. Description of the Prior Art
AT&T as well as MCI and U.S. Sprint now provide services referred to as video teleconferencing. The equipment, systems and cost may differ between vendors to achieve a desired result function wherein two or more groups of conferees at different locations are able to view each other while conducting a real time conference and wherein different types of information are exchanged. Video TeleConferencing (VTC) differs from Business TeleVision (BTV) in that business TV is best described as Receive Only Viewing (ROV) by large audiences at remote locations of a single TV program usually originating at a single source. When business TV is combined with call in telephone questions, etc. from the live audience the results are similar to TV talk shows that take questions via telephone from the viewing audience.
Teleconferencing and business TV do not require as broad an information band as commercial TV. Commercial satellite TV in the United States employs an analog FM format requiring 36 megahertz bandwidth. Using digital data compression techniques it is presently possible to transmit sufficient data for video teleconferencing at a bandwidth of 768 kilobits per second with 384 kilobits per second transmission predicted for the future. The lower transmission rates are accompanied by lower network transmission cost without information degradation.
There are presently four or five major competing transmission network services whose cost are constantly being reduced so that no one dedicated VTC/BTV system is capable of taking advantage of all of the desirable features of any one system over a period of time.
Thus, it would be highly desirable to provide a teleconferencing system which may be used for business television and is flexible enough to accept input from and output to the various competitive networks so that the most efficient and most economical available network can be programmed for use with the present invention system.